What is the Ideal Blog Post Length?

On Concurring Opinions, Lawrence Cunningham asks "is there an optimal length for a blog post or an ideal depth?' "Can posts be too short and snappy or too long and laborious?" He notes that "some posts around the blogosphere are surprisingly brief, perhaps a mere sentence noticing an article or book publication or other event, while others probe deeply through layers of challenging ideas requiring up to 4,000 words to feature." In other words, some posts are written for current awareness purposes, others offer analysis and commentary.

I think the question is devoid of context if one doesn't take into account the type of content and intention of the post. Certainly some posts can be long and laborious if the audience for blogs is viewed as a short attention span, skim-over-and-move-on publishing medium but the content shift to more analysis and commentary is a noticable blogosphere trend. My hunch is blog writers may have to take a tip from journalism to engage some people to read longer posts, namely, write a first paragraph that captures the essence of the entire post like newspaper reporters and editors do. [JH]